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Ítem Multi-environment multi-QTL association mapping identifies disease resistance QTL in barley germplasm from Latin America(Springer Nature, 2014-12-30) Gutiérrez, Lucia; Germán, Silvia; Pereyra, Silvia; Hayes, Patrick M.; Pérez, Carlos A.; Capettini, Flavio; Locatelli, Andres; Berberian, Natalia M.; Falconi, Esteban E.; Estrada Zúniga, Rigoberto; Fros, Dario; Gonza Cusipuma, Víctor Antonio; Altamirano Vasquez, Hernan; Huerta Espino, Julio; Neyra Valdez, Edgar; Orjeda, Gisella; Sandoval Islas, Sergio; Singh, Ravi; Turkington, Kelly; Castro, Ariel J.Diseases represent a major constraint for barley (Hordeum vulgare L.) production in Latin America. Spot blotch (caused by Cochliobolus sativus), stripe rust (caused by Puccinia striiformis f.sp. hordei) and leaf rust (caused by Puccinia hordei) are three of the most important diseases that affect the crop in the region. Since fungicide application is not an economically or environmentally sound solution, the development of durably resistant varieties is a priority for breeding programs. Therefore, new resistance sources are needed. The objective of this work was to detect genomic regions associated with field level plant resistance to spot blotch, stripe rust, and leaf rust in Latin American germplasm. Disease severities measured in multi-environment trials across the Americas and 1,096 SNPs in a population of 360 genotypes were used to identify genomic regions associated with disease resistance. Optimized experimental design and spatial modeling were used in each trial to estimate genotypic means. Genome-Wide Association Mapping (GWAS) in each environment was used to detect Quantitative Trait Loci (QTL). All significant environment-specific QTL were subsequently included in a multi-environment-multi-QTL (MEMQ) model. Geographical origin and inflorescence type were the main determinants of population structure. Spot blotch severity was low to intermediate while leaf and stripe rust severity was high in all environments. Mega-environments were defined by locations for spot blotch and leaf rust. Significant marker-trait associations for spot blotch (9 QTL), leaf (6 QTL) and stripe rust (7 QTL) and both global and environment-specific QTL were detected that will be useful for future breeding efforts.Ítem Co-benefits of soil carbon protection for invertebrate conservation(EL SEVIER, 2020-11-13) Flores Rios, Angelli; Thomas, Evert; Peri, Pablo P.; Amelung, Wulf; Duarte Guardia, Sandra; Borchard, Nils; Lizárraga Travaglini, Alfonso Diulio; Vélez Azañero, Armando; Sheil, Douglas; Tscharntke, Teja; Steffan Dewenter, Ingolf; Ladd, BrentonThe global decline in invertebrate diversity requires urgent conservation interventions. However, identifying priority conservation areas for invertebrates remains a significant challenge. We hypothesized that aligning the conservation of invertebrate biodiversity with climate change mitigation ofer offers a solution. As both soil carbon storage and invertebrate biodiversity are positively influenced by plant diversity and productivity, a positive correlation can also be expected between SOC and invertebrate biodiversity. Drawing on >10,000 invertebrate observations organized into functional groups, and site-specific soil organic Carbon (SOC) measurements from Patagonia, the Peruvian Andes, and montane tropical rainforest, we examined the role of climate, soil, topographical position and land use for prediction of invertebrate biodiversity. We found that taxonomic and functional invertebrate diversity and abundance closely correlate with SOC stocks within ecosystems. Topographical position of sites, which was partly associated with SOC, was also important, whereas land use was of subordinate importance. We conclude that recent advances in predicting and mapping SOC can guide the identification of habitats within landscapes with high biodiversity and conservation value for invertebrates. Our findings stress the importance of linking global climate change mitigation initiatives that aim to preserve and restore SOC to efforts aimed at improving the conservation of invertebrates and the ecosystem services they provide, for the realization of mutual climate and biodiversity benefits.Ítem Traditional processing of black and white chuño in the peruvian andes: regional variants and effect on the mineral content of native potato cultivars(Springer Nature, 2010-08-11) De Haan, Stef; Burgos, Gabriela; Arcos Pineda, Jesús; Ccanto, Raul; Scurrah, Maria; Salas Murrugarra, Elisa del Carmen; Bonierbale, MeridethTraditional Processing of Black and White Chuño in the Peruvian Andes: Regional Variants and Effect on the Mineral Content of Native Potato Cultivars. Farmers in the high Andes of central to southern Peru and Bolivia typically freeze-dry potatoes to obtain chuño. Processing of so-called black chuño follows tending, treading, freezing, and drying. The making of white chuño is generally more complex and involves exposure of tubers to water. Regional variants exist for each of these processes, yet their influence on the nutritional composition of native potato cultivars is little known. Tubers belonging to four distinct cultivars and produced in a replicated trial under uniform conditions were processed into four types of chuño following standard traditional procedures (farmer-managed). These regional variants were documented, and the dry matter, iron, zinc, calcium, potassium, phosphorus, magnesium, and sodium content of the four resulting different types of boiled chuño determined at the International Potato Center's Quality and Nutrition Laboratory (Lima, Peru). Content values were compared with those of boiled (unprocessed) tubers from the same experiment. Regional variants of processing are to a large extent determined by tradition, environmental condition, and market demand. The zinc, potassium, phosphorus, and magnesium content of all types of chuño decreases in comparison with unprocessed tubers. Concentrations of these same minerals decrease more drastically for white as compared to black chuño. The effect of the four regional variants of freeze-drying on the dry matter, iron, calcium, and sodium content of chuño differs by process and/or cultivar.Ítem Genetic diversity in creole pigs in south central Peru(Springer, 2023-11-30) Luna, Rosa; Acuña Rodríguez, Wendy; Gutiérrez, Gustavo; Castro Muñoz, María del Rosario; Veli Rivera, Eudosio AmancioThe creole pigs represent 67% of the national population in Peru. They are a source of economic income in rural communities, and due to their rusticity, they are not much labor demanding. However, knowledge about its genetic diversity remains scarce. The objective of this study was to determine the population structure and genetic diversity of creole pigs from rural communities in south central Peru. Thirteen microsatellites were used to characterize 120 creole pigs from the departments of Ayacucho (57) and Apurimac (63). The samples were taken from hair follicles and ear tissue. Nine microsatellites were highly polymorphic and informative (PIC > 0.5) for both departments. The Ayacucho population had a mean number of alleles (MNA) and expected heterozygosity (HE) of 8.8 and 0.68, respectively, while in the Apurimac population, these were 8.9 and 0.71, respectively. Both populations showed in less than 50% of their loci a deviation from Hardy–Weinberg equilibrium. There was a moderate genetic structure according to the analysis of molecular variance and the FST statistics (0.06), which was corroborated by Bayesian methods. In conclusion, the genetic diversity was mostly due to the intrapopulation variance (91%). Some individuals from Ayacucho shared similar alleles with those from Apurimac. This latter result may be due to their geographic proximity and the introduction of the same new exotic breeds. This is the first research on the genetic diversity of creole pigs in south central Peru. In fact, this study could serve as a basis for conservation strategies and actions in this region.Ítem Performance and physiological quality of Escallonia resinosa seeds: prospects for their use in reforestation and restoration(John Wiley and Sons Inc, 2022-12-10) Huayta Hinojosa, Luis David; Nolasco Lozano, Emily Gisella Ninfa; Guerra, Damaris; Hermoza Gamboa, Joel; Quispe Melgar, Harold RusbelthIn the Andes, many native forest species are not used in reforestation or restoration programs mainly due to a lack of information about their propagation. In this study, we evaluated the performance of the seeds of Escallonia resinosa by analyzing fruit and seed productivity and characteristics, seed physiological quality, and the germination rate of seeds collected at different stages of fruit physiological maturity, using tetrazolium and standard germination tests. Our results show an estimated production (mean ± SD) of 34,252.5 ± 25,900 fruits per tree and 26.5 ± 20 million seeds per tree. Seed length was 1.0 ± 0.13 mm and seed weight was 12.4 ± 1 μg. We recognized two different morphological types of seeds: Type I seeds (lacking testa) were unviable, whereas all Type II seeds (with testa) germinated. Seed viability and germination rates were 10.5 and 48.6%, respectively; therefore, the viability test underestimated the actual germination rate. Morphological or microsite variables of the parent tree did not influence seed viability or germination. Germination rates were highest (41.8 ± 2.5%) for the seeds of fruits harvested at the initial maturity stage (green fruits). Our results show that E. resinosa is a species with potential for reforestation and restoration projects in the Andes: it has high seed production and good germination performance, and seeds can be harvested from fruits collected at different stages of physiological maturity.Ítem Conversion of lowland tropical forests to tree cash crop plantations loses up to one-half of stored soil organic carbon(Stanford University, 2015-08-11) Van Straaten, Oliver; Corre, Marife D.; Wolf, Katrin; Tchienkoua, Martin; Cuellar Bautista, José Eloy; Matthews, Robin; Veldkamp, EdzoTropical deforestation for the establishment of tree cash crop plantations causes significant alterations to soil organic carbon (SOC) dynamics. Despite this recognition, the current Intergovernmental Panel on Climate Change (IPCC) tier 1 method has a SOC change factor of 1 (no SOC loss) for conversion of forests to perennial tree crops, because of scarcity of SOC data. In this pantropic study, conducted in active deforestation regions of Indonesia, Cameroon, and Peru, we quantified the impact of forest conversion to oil palm (Elaeis guineensis), rubber (Hevea brasiliensis), and cacao (Theobroma cacao) agroforestry plantations on SOC stocks within 3-m depth in deeply weathered mineral soils. We also investigated the underlying biophysical controls regulating SOC stock changes. Using a space-for-time substitution approach, we compared SOC stocks from paired forests (n = 32) and adjacent plantations (n = 54). Our study showed that deforestation for tree plantations decreased SOC stocks by up to 50%. The key variable that predicted SOC changes across plantations was the amount of SOC present in the forest before conversion—the higher the initial SOC, the higher the loss. Decreases in SOC stocks were most pronounced in the topsoil, although older plantations showed considerable SOC losses below 1-m depth. Our results suggest that (i) the IPCC tier 1 method should be revised from its current SOC change factor of 1 to 0.6 ± 0.1 for oil palm and cacao agroforestry plantations and 0.8 ± 0.3 for rubber plantations in the humid tropics; and (ii) land use management policies should protect natural forests on carbon-rich mineral soils to minimize SOC losses.Ítem Effect of production environment, genotype and process on the mineral content of native bitter potato cultivars converted into white chuño(John Wiley & Sons, 2012-08-15) De Haan, Stef; Burgos, Gabriela; Ccanto, Raul; Arcos Pineda, Jesús; Scurrah, Maria; Salas Murrugarra, Elisa del Carmen; Bonierbale, MeridethBACKGROUND: Variables and interaction effects affecting the mineral concentration of Andean bitter potatoes converted into so-called white chuño are unknown. We report on the effect of three contrasting production environments (E) on the dry matter (DM), zinc, iron, calcium, potassium, magnesium, phosphorus and sodium concentration of four potato native bitter genotypes (G) processed (P) into two different ‘types’ of white chuño. RESULTS: The DM content and iron, calcium, magnesium and sodium concentration of white chuño are significantly dependent on E, G, P, and E × G × P interaction (predominantly at P < 0.01). In particular, the DM content and calcium concentration are influenced by all variables and possible interaction effects. The zinc and potassium concentration are not significantly dependent on E × G, G × P or E × G × P interaction effects, while the phosphorus concentration is not significantly affected by the G × P or E × G × P interaction effect. Zinc, phosphorus and magnesium concentrations decrease in the ranges of 48.3-81.5%, 61.2-73.0% and 62.0-89.7% respectively. The decrease in potassium is particularly severe, with 122- to 330-fold losses. Iron and calcium increase by 11.2-45.6% and 74.5-714.9% respectively. CONCLUSION: E, G, P, and various interaction effects influence the mineral concentration of traditionally processed tubers. We speculate that mineral losses are caused by leaching, while increases of iron and calcium are a likely result of absorption.Ítem Pathogenicity of Heterorhabditis bacteriophora in ultraviolet light–irradiated agar suspension on Spodoptera frugiperda (Lepidoptera: Noctuidae) larvae(Georgia Entomological Society, 2023-09-08) Pérez Tesén, Edgar Darwin; Rodas Adrianzén, Jennifher Elizabeth; Chávez Cabrera, Alexander; Neira de Perales, María ElenaSpodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is an economically important pest of variety of crops, including maize (Zea mays L.), rice (Oryza sativa L.), and cotton (Gossypium spp.). Conventional chemical insecticides are usually used for management of this pest; however, a viable alternative is the use of microbial agents or their biological products, such as entomopathogenic nematodes. Their efficacy, however, is affected by abiotic conditions including ultraviolet (UV) light and desiccation. It is therefore necessary to develop formulations that preserve or extend the viability of the agent or product while facilitating ease of application. This laboratory study was conducted to determine the pathogenicity of the nematode Heterorhabditis bacteriophora (Poinar) against S. frugiperda third-instar larvae. Infective juveniles (IJs) of the nematode were tested at a concentration of 350 IJs/ml in two substrates (water and 0.1% [w/v] agar suspension) with four periods of exposure (0, 5, 10 and 15 min) to UV radiation at 253.7 nm. Each of the eight treatments included 40 larvae, with each treatment replicated three times in a completely randomized design (two factors of type of medium and UV exposure time). We determined that the 0.1% (w/v) agar suspension, compared with the water substrate, protected the IJs from harmful UV light and thus improved the survival and pathogenicity of the IJs against third-instar S. frugiperda.Ítem Inheritance of white, black and brown coat colours in alpaca (Vicuna pacos L.)(Elsevier, 2011-05-10) Valbonesi, Alessandro; Apaza, Nolberto; La Manna, Vincenzo; Gonzáles Castillo, Mario Lino; Huanca Mamani, Teodosio; Renieri, CarloAn experimental trial of the segregation of white vs. pigmented and black vs. brown colours in alpacas was conducted at the Peruvian INIA Quimsachata Experimental Station. One hundred and forty five offspring were born from the following matings: 4 white sires × 36 white dams, 4 white sires × 39 pigmented dams, and 9 pigmented sires × 70 pigmented dams. Among these last matings were, 4 black sires × 25 black dams, 2 black sires × 20 brown dams, and 3 brown sires × 25 brown dams. Statistical tests validate that the inheritance of white is due to a single gene which is dominant over pigmentation, without any modifying effect and independent of segregation of black and brown patterns. However, the evidence does not support a simple dominant inheritance of the black vs. brown.Ítem Cooling of alpaca spermatozoa using an extender with the addition of different percentages of seminal plasma(Elsevier, 2023-12-06) Bertuzzi, Mariana Lucía; Torres Mamani, Edita Yola; Pérez Durand, Manuel Guido; Huanca Mamani, Teodosio; Giuliano, Susana María; Carretero, María IgnaciaThe objective of this study was to evaluate the effect of the addition of different percentages of seminal plasma (SP) during the cooling at 5 °C of alpaca spermatozoa from vas deferens. Fifteen pools of sperm from vas deferens were evaluated and then divided into four aliquots that were diluted to a final concentration of 30 × 106 sperm/ml with either: (1) Tris with 20% egg yolk (T-EY) (control, 0% SP), (2) T-EY with 10% SP, (3) T-EY with 25% SP, and (4) T-EY with 50% SP. Samples were cooled at 5 °C and the following sperm parameters were evaluated after 24 and 48 h of storage: motility, viability, membrane function, acrosome integrity, morphology, and chromatin condensation. Motility was also evaluated after 72 h of storage. A significant decrease in progressive and total sperm motility was observed in samples cooled with 50% SP with respect to all diluted samples, while these parameters were preserved in samples cooled with 0%, 10%, and 25% SP. The percentages of sperm viability, normal morphology, and highly condensed chromatin did not change after the cooling process and were similar between cooled samples. Although a significant decrease was observed in the percentage of spermatozoa with functional membranes and with an intact acrosome in all refrigerated samples compared to raw sperm, the greatest decrease was observed in samples cooled with 50% SP. No advantage was observed from the addition of SP to alpaca spermatozoa obtained from vas deferens and being cooled. In addition, to preserve the sperm motility of cooled samples for up to 72 h, it should be recommended to include a 10% SP in the extender.